Photo: Quintin Soloviev · CC BY 4.0Cornwall faces fewer hazards than 88% of Canadian towns
The national fire record shows next to nothing around Cornwall, 0% of the land within 25 km since 1986 (0.000% a year). Shaking is about as much of a worry in Cornwall as in most places, at $0.019 a year per $1,000 of building value ($0.030 typical). In Health Canada’s survey, just 3.5% of homes tested in the area exceeded 200 Bq/m³ (6.6% typical). Hazard risk gives Cornwall a grade of A, from earthquakes and radon alone.
What stands out about Cornwall’s hazards
Four national sources, each read for Cornwall: earthquakes, radon, past fires and flood studies.
What Cornwall faces
Each hazard against its own yardstick; meters run from low to high on that yardstick.
Wildfire
Earthquakes
Radon
Flood study
Hazard risk in Cornwall: A
Earthquake risk and radon make Cornwall’s grade; wildfire can only lower it, never raise it, and flood studies are listed but not scored.
Its place: #2 of 12 on Prince Edward Island and #511 of 2,589 Canadian towns.
How sure: Earthquake losses are a model’s expectation over many years, not a forecast for any one. Small fires and grass fires are largely missing from the national burned-area record.
Wildfire is rare near Cornwall: 0% of the land within 25 km burned since 1986, 0% within 5 km
Fires mapped since 1986 around where Cornwall’s residents live, and the fuel next to their homes.
In a typical year 0.000% of the land near Cornwall burns; the typical Canadian town sees 0.000%, and both are low.
There is forest near Cornwall’s homes (5.5% within 5 km) and more of it further out (18% within 25 km).
Shares of land within 5 and 25 km of populated blocks: burned at least once in 1986–2025 (CWFIS burned-area composite), forest fuel and grass (fire behaviour fuel types, 2026, 250 m grid).
Burn rate a year, towns on Prince Edward Island · highest of 12
Fire is all but absent around the 12 towns on Prince Edward Island, Cornwall included.
Each bar: the yearly average share of land within 25 km of a town’s homes that burned, 1986–2025 (CWFIS); the seven highest towns of 2,500 people or more.
92% of Canada’s 2,610 towns are in the low band and 7.5% above it; Cornwall is among the many where the yearly burn rate rounds to zero.
Bands of the yearly burn rate: low under 0.05%, moderate under 0.25%, high under 1%, very high 1% or more; towns of 2,500 people or more.
Fire danger and active fires (CWFIS)
Canadian Wildland Fire Information System: National Burned Area Composite 1986–2025 and fire behaviour fuel types (2026), Natural Resources Canada. Measured within 25 km and 5 km of each populated dissemination area; past fire, not a forecast.
2 flood studies cover Cornwall, the newest from Department of Environment, Energy and Climate Action - Government of Prince Edward Island
Flood studies whose area touches Cornwall, from NRCan’s inventory, each linked to its owner.
Department of Environment, Energy and Climate Action - Government of Prince Edward Island and others have studied flooding in areas that include Cornwall: 2 studies, the latest from 2024.
| Study | By | Year | Status |
|---|---|---|---|
| PEI Pluvial Flood Mapping | Department of Environment, Energy and Climate Action - Government of Prince Edward Island | 2024 | final |
| Prince Edward Island Coastal Hazards | Province of PEI, Department of Environment, Energy and Climate Action | 2021 | final |
Towns with a flood study on file
Its flood study puts Cornwall with 100% of towns on Prince Edward Island; Canada’s share is 58%.
NRCan Canada Flood Map Inventory: a study footprint touching the town’s boundary; towns of 2,500 people or more.
Flood is shown here, never graded: a study says where a map exists, not how many of Cornwall’s homes stand in a flood zone.
The inventory’s own caution (NRCan): “The Canada Flood Map (CFM) does not include every flood hazard map in Canada and may be incomplete or contain inaccuracies. It should not be relied upon as the official source of flood mapping information. Furthermore, if a map appears to be missing, this does not necessarily mean that the area has never been mapped. For the official version of a map, updated information, or confirmation of applicable regulations, please contact the local authority responsible for flood mapping.”
Natural Resources Canada, Canada Flood Map Inventory; links go to each study’s owner.
Earthquakes cost buildings in Cornwall $0.019 per $1,000 a year
NRCan’s seismic risk model: the damage shaking is expected to do to buildings each year, on average over many years.
Nothing unusual about Cornwall’s ground: $0.019 against a typical $0.030, 0.6 times.
Shaking damage a year per $1,000 of building value
The median on Prince Edward Island is $0.020; Cornwall, at $0.019, is right beside it, and O'Leary tops the list at $0.034.
NRCan seismic risk model (2022): mean yearly building loss per $1,000 of value; medians of towns of 2,500 people or more.
Most of Canada’s 2,611 towns (66%) face more earthquake damage than Cornwall.
Each column: the share of Canada’s towns of 2,500 people or more in that range of yearly loss per $1,000 (NRCan, 2022).
Roads, pipes and bridges aren’t in Cornwall’s figure, nor landslides or tsunami: it is buildings and shaking.
Natural Resources Canada, Canada’s Seismic Risk Model (2022), by census subdivision (2016 boundaries; a few 2021 subdivisions take their residents’ mean).
Radon runs low around Cornwall: 3.5% of tested homes over the guideline
Health Canada’s survey of long-term home tests: the share above the 200 Bq/m³ guideline. · Area-wide: radon tests, counted over the Prince Edward Island Health Region
A lower share than most: 3.5% of tested homes around Cornwall, the typical Canadian town 6.6%.
Tested homes over 200 Bq/m³
Over 600 Bq/m³
Around Cornwall, 3.5% of tests topped the guideline, about the same as the typical town on Prince Edward Island (3.5%).
Health Canada radon survey (2009–2011), by 2007 health region; medians of towns of 2,500 people or more.
Under 5% puts Cornwall with 37% of Canada’s 2,611 towns; 63% have more high tests.
Each bar: the share of Canada’s towns of 2,500 people or more whose survey area had that share of tests over 200 Bq/m³.
A survey sample isn’t a map: any home in Cornwall can be high, and a three-month test is the only way to know.
Health Canada, Cross-Canada Survey of Radon Concentrations in Homes (2009–2011).
Weather and fire alerts for Cornwall
Environment and Climate Change Canada issues the weather alerts for Cornwall; Alert Ready carries the urgent ones to phones, radio and TV.
| Alert | What it means |
|---|---|
| Warning | Severe weather is happening or about to: act now. |
| Watch | Conditions favour severe weather: be ready. |
| Advisory | Weather that is less severe but could disrupt the day. |
| Special weather statement | Unusual weather worth knowing about. |
| Special air quality statement | Poor air, often wildfire smoke. |
For fires near Cornwall, the national fire information system maps danger and active fires daily; local authorities give any evacuation order.
Weather alerts (ECCC) · Alert Ready · Fire danger and active fires (CWFIS)
Hazards in the places around Cornwall
The same four hazards for the places next door.
| Town | Wildfire | Quake $/1,000 | Radon | Flood study |
|---|---|---|---|---|
| Cornwall | Low | $0.019 | 3.5% | Yes |
| Charlottetown 48,118 · 5.4 km | Low | $0.019 | 3.5% | Yes |
| Stratford 13,152 · 8.3 km | Low | $0.021 | 3.5% | Yes |
| Kingston 1,308 · 8.8 km | Low | $0.018 | 3.5% | Yes |
| Miltonvale Park 1,279 · 9.3 km | Low | $0.019 | 3.5% | Yes |
| West River 4,155 · 9.9 km | Low | $0.016 | 3.5% | Yes |
| Crossroads 2,366 · 13 km | Low | $0.020 | 3.5% | Yes |
None of the places around has more fire nearby than Cornwall (low); Charlottetown comes closest (low).
Radon is the survey area’s figure, so neighbours in one area share it.
Get ready for what Cornwall faces
Practical steps for Cornwall’s hazards, most pressing first.
- Test for three months in winter.
- Over 200 Bq/m³: fix it.
- Kits are cheap; pros test too.
- Never drive through floodwater.
- Move papers and medicines upstairs.
- Ask whether your street is mapped.
- Clear needles and wood nearby.
- Keep a grab-and-go bag ready.
- In smoke, stay in; filter air.
- Has it had a radon test?
- Check the address on the flood map.
- Are flood and wildfire insured?
What this data can and can’t tell you
- Flood studies aren’t flood zones. The flood inventory points to maps; it is incomplete and not the official source, so ask the municipality about any street in Cornwall.
- Earthquakes are modelled. Shaking damage is modelled from the ground, the buildings and the odds of each quake, and published for whole subdivisions such as Cornwall’s.
- Radon is a survey. Health Canada’s survey tested some 14,000 homes over three months; until postal-area boundaries are loaded, Cornwall takes its 2007 health region’s share.
- Wildfire counts one way. The wildfire figure is the share of land within 25 km of Cornwall’s homes burned each year from 1986 to 2025, past fire rather than a forecast, and it can only lower Risk.
Questions about flooding and hazards in Cornwall
Does Cornwall flood?
The inventory lists a study touching Cornwall; whether a given street floods is on that map, not in the grade.
Is Cornwall at risk of wildfire?
The burned-area record shows next to nothing around Cornwall (0% within 25 km since 1986), so its band is low.
How big is the earthquake risk in Cornwall?
About $0.019 a year per $1,000 of building value, NRCan’s long-run expectation for Cornwall.
How is Cornwall’s Hazard risk Grade worked out?
Hazard risk gives Cornwall A, weighing earthquakes and radon and counting wildfire only against it.
Is radon a problem in Cornwall?
3.5% of the 113 homes Health Canada tested around Cornwall topped the guideline; your own house needs its own test.
Seismic risk: Natural Resources Canada. Radon: Health Canada. Wildfire: Canadian Wildland Fire Information System. Flood studies: Natural Resources Canada, Canada Flood Map Inventory. Contains information licensed under the Open Government Licence – Canada.
Sources: NRCan, Canada’s Seismic Risk Model 2022 · Health Canada, Cross-Canada Survey of Radon Concentrations in Homes · CWFIS, National Burned Area Composite and FBP fuel types · NRCan, Canada Flood Map Inventory. Under the Statistics Canada Open Licence.
Adapted from Statistics Canada (Census of Population 2021, population estimates 2025, 2021 census boundaries) under the Statistics Canada Open Licence; this does not constitute an endorsement by Statistics Canada. Neighbourhood names in some cities © OpenStreetMap contributors (ODbL).